Closed molding tool

ABSTRACT

A flexible molding component used with a base mold improves on existing methods of forming fiber reinforced composite parts. The molding component is formed of a flexible body structure having an interfacing surface and a perimeter region including a perimeter seal configured for sealing engagement with the base mold. Resin and vacuum distribution channels are formed in the interfacing surface to deliver resin to a fiber lay up disposed on the base mold and draw the resin across and through the lay up, respectively, to properly mix the resin/fiber combination which forms the desired part. Application of the vacuum causes the perimeter seal of the flexible body structure to sealingly engage with the base mold to enclose materials between the body structure and the mold, as well as causing the interfacing surface to draw against the resin/fiber combination and the mold to shape the combination into the desired part.

CROSS-REFERENCE TO RELATED APPLICATIONS

None.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable.

BACKGROUND OF THE INVENTION

The production of fiber reinforced composite components, and inparticular those components formed of a fiber/resin combination, havetraditionally been accomplished by a number of open and closed moldinglamination processes, or variations of each. Examples of thesecomponents include those used in the boating industry; such as fiberreinforced plastic sheets and parts with a compound shape used tomanufacture a hull for a watercraft. These molding processes all involvea fiber reinforcement (e.g., fiberglass pieces) being laid up against amold (e.g., a female mold) that provides the desired shape for thecomponent, and the impregnation of the fiber with resin or a similarmaterial. After curing, the resin/fiber combination forms a finishedpart that can be removed from the mold. Apart from these similarities,however, molding processes are distinct in the efficiencies provided byeach, as well as in the disadvantages or tradeoffs encountered whenchoosing a molding process for fabricating a specific type or run of acomponent.

Open molding lamination processes are traditionally more labor intensivethan other molding processes and usually produce less consistent partquality in high volume production. Open molding processes are alsofalling out of favor with manufacturers due to the high emissions ofvolatile organic compounds (VOC) realized in part production. Oneproposed solution was to use component materials that resulted in fewerVOC emissions, but this has resulted in parts having poor physicalcharacteristics. Still, despite these disadvantages, open moldingprocesses—along with vacuum bag molding—are generally the only widelyused molding processes that are capable of producing low volume or lowrun parts in a cost effective manner.

Vacuum bag molding is a type of closed molding technique that involvesforming a thin flexible bag to cover the mold upon which the fiber layup is positioned. The edges of the bag are then clamped, taped orotherwise secured to the mold to form a sealed envelope surrounding thefiber lay up. One or more vacuum supply lines are usually installedwithin the bag to apply a vacuum on the bag interior concomitant withcatalyzed liquid plastic or resin being introduced into the bag througha resin supply line to impregnate the fiber lay up. The vacuum draws thebag against the resin/fiber combination and surface of the mold to shapethe combination into the desired part. The resin supply lines aretypically positioned to introduce resin either at the perimeter of thepart such that the vacuum supply line draws the resin across and throughthe fiber lay up towards the center of the part, or vice versa, with theresin introduced at the center of the part and vacuum drawing the resintowards the perimeter of the part. Vacuum bag molding can usually becategorized as either utilizing, (1) a thin disposable bag made fromsheet film, or (2) a reusable bag made from silicone, both of which areflexible bags. Because the resin and fiber are essentially sealed offfrom the surrounding environment, vacuum bag molding techniques exposetool operators to significantly fewer VOC's than with open moldingprocesses, which is a significant reason why vacuum bag techniques havegained interest in recent years.

When using a disposable vacuum bag, a peel ply release film and a resinflow/bleeder media must often be stacked atop the fiber lay up below thebag because of the nature of the thin sheet film to conform very tightlyto the fiber layer up and make resin flow very difficult. The resinflow/bleeder media facilitates flow of the resin across and through thefiber lay up in a timely manner by essentially forming a resinpassageway, and the peel ply film ensures that both the media and peelply layer itself may be easily pulled off of the finished part withoutundue effort. Additionally, resin and vacuum distribution linesextending from the supply lines and routed beneath the vacuum bag acrossthe mold are often needed in addition to the resin flow/bleeder media toproperly distribute the resin and apply the vacuum draw beneath thetightly drawn thin sheet film. Also, adhesive sealant tape is typicallyapplied around the perimeter of the bag to form an airtight seal withthe mold and facilitate proper vacuum operation.

Despite the high quality of the part produced using disposable vacuumbag molding techniques (i.e., having a high fiber to resin ratio),certain disadvantages are apparent. For example, many of theaforementioned components used in disposable vacuum bagtechniques—including the vacuum bag having resin and vacuum supply linesintegrally formed therewith, the resin flow/bleeder media, the peel plyfilm, the resin and vacuum distribution lines and the adhesive sealanttape—are disposed of after molding only a single part, making thistechnique prohibitively expensive for all but high margin partsmanufacturing. Significant labor is also necessary when using adisposable bag, as the bag must be made by hand to fit the particularbase mold and also installed by hand with the resin flow/bleeder media,peel ply film, resin and vacuum distribution lines and sealant tape atthe proper positions for the vacuum draw and resin impregnation of thefiber lay up to work. Furthermore, if the female mold has a complexshape, many pieces of sheet film may need to be cut and bonded togetherwith sealant tape to produce a bag with the desired shape, therebysignificantly increasing manufacturing time per part as compared to openmolding processes.

Silicone bags implemented in vacuum bag molding techniques provide thedistinct advantage of being reusable, such that multiple parts may beproduced with the mold using just one bag. This provides a saving inlabor as compared to disposable sheet film bags. The silicone bag istypically fabricated from silicone sheet or a brushable silicone liquid,but because silicone alone usually does not have enough strength towithstand the vacuum draw in the molding process, a reinforcement suchas nylon mesh or other materials is often laminated with the silicon.Another problem with silicone is that even with a reinforcement, the bagtends to have a relatively short life and is useful for only small partproduction runs; the silicone bag is easily damaged in the productionenvironment, difficult to have resin and vacuum supply and distributionlines integrated therewith, and tends to expand dimensionally over anumber of production runs, requiring significant maintenance to keep thebag usable for the molding process. As with disposable vacuum bags,adhesive sealant tape or other adhesives must still be used when sealingthe silicone bag perimeter to the mold to form an airtight seal forvacuum operation. Silicone materials are also expensive, leading to ahigh initial cost of fabricating the vacuum bag. Also, silicone bagsrequire oven curing in the fabrication of the more durable materials,which adds further to the cost of the process with the additional time,energy and equipment requirements.

Yet another closed molding process, resin transfer molding, involvesusing rigid male and female molds together to produce fiber reinforcedcomposite parts. A fiber lay up is placed on the female mold and themale mold is brought into contact with the female mold and clamped orotherwise secured therewith so that a closed space is formed between themolds. Then, a mixed resin and catalyst are injected into the closedspace under relatively low pressure. Upon curing of the resin, the moldsare separated and the part is removed. The resin transfer moldingprocess is more environmentally friendly than traditional open moldingprocesses, with the capture of any VOC's present in the closed spaceoccurring before the molds are separated to reveal the finished part.One significant disadvantage of resin transfer molding, however, is thatbecause the male and female molds are rigid, if the fiber load of thelay up is not precisely the correct quantity at the correct position,structural weakness in the part occur. For example, “dry spots” occurwhere the resin cannot flow to during the injection process if the fiberdensity is too high, and if the fiber density is too low, a spot filledwith resin will develop. Both dry spots and resin filled spots infinished parts are susceptible to fracture or other structural failuresat relatively low force loads. These structural weaknesses are even moreimportant when fabricating large parts, such as boat hull components,where the weight of the part itself may facilitate structural failures.Matched, rigid tooling is very expensive to produce and, therefore, theprocess is less amenable to changes that may be required for structural,process, or styling updates.

Current closed molding lamination techniques do not provide aneconomical and reliable solution for fabricating fiber reinforcedcomposite parts, especially with respect to small to medium part runs. Amolding technique is needed that balances tool cost considerations withreliability and speed in the part fabrication process.

BRIEF SUMMARY OF THE INVENTION

A flexible molding component is provided for use with a base mold toform a fiber reinforced composite part. The molding component tool isformed of a flexible body structure having an interfacing surface and aperimeter region including a perimeter seal configured for sealingengagement with the base mold. Resin and vacuum distribution channelsare formed in the interfacing surface to deliver resin to a fiber lay updisposed on the base mold and draw the resin across and through the layup, respectively, to properly mix the resin/fiber combination whichforms the desired part. Application of the vacuum causes the perimeterseal of the flexible body structure to sealingly engage with the basemold to enclose material between the body structure and the mold, aswell as causing the body structure interfacing surface to draw againstthe resin/fiber combination and the mold to shape the materialscombination into the desired part. A standoff having a plurality ofpassages formed therein may also be formed in the interfacing surface ofthe body structure to facilitate the movement of resin between resindistribution channels or otherwise across and through the fiber lay uptowards regions where vacuum pressure is applied. To form the bodystructure with enough flexibility to draw against the mold and generatea sufficient engagement of the perimeter seal, but firm enough as to notrequire the use of resin flow/bleeder media to enable proper resin flow,the molding component may be formed of a material such as polyurea,polyurethane, a polyurea/polyurethane compound, or materials withsimilar physical characteristics.

The molding component tool provides many advantages in closed moldingprocesses, including: reusability for producing a large run of parts;having sufficient flexibility and flange requirements to be compatiblewith many existing “A” surface open molding process tooling (typically,but not always, a conventional female mold); incorporating integral,molded vacuum perimeter seals, resin and vacuum distribution channels,and standoff passageways into the flexible body structure as acontinuously molded single unit, without the need to separately fitcomponents to the body structure or fabricate internal toolreinforcements; having a structural design that can be engineered togenerate a high degree of design and manufacturing tolerance flexibilityin molding parts, such as various surface finishes, various degrees ofcontour conformability, molding pressure variations, mold elongation andcompression, or other physical properties applied either to a part as awhole, or certain portions of the part, without requiring toolmodifications or replacement; being formed of materials that aresprayable, brushable, castable and/or pourable to form the componenttool; fabrication without the added expense of providing large curingovens; having increased durability and being essentially chemicallyinert—so as not to bond with polyester and other commonly usedresins—and easier to repair than conventional silicone bags; andacceptable to further possessing compatibility with ultra violet (UV)and/or forced thermal curing of gel coats and resins.

Fiber reinforced composite components fabricated according to thepresent invention may find application in many industries, includingmarine, automotive, recreational vehicle, aircraft, industrial, and thelike. The molding component tool enables a closed molding process to beimplemented that reduces expense and the labor of replacing disposabletooling (e.g., vacuum bag and associated components), is moreenvironmentally friendly than open molding processes, uses tooling thatis more durable, less expensive, and less complex than silicone vacuumbag tooling, and provides a high degree of consistency in finished partstructural integrity as compared to resin transfer molding techniques.The molding tool provides the capability to close mold parts with manybase mold tools used with the less desirable open molding methodologywithout costly base mold modification or replacement. Due to theflexible nature of the tool, significant part design flexibility existswithout the need to manufacture a new “B” tool.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a perspective view of a molding component of the presentinvention interfacing with a base mold to form a fiber reinforcedcomposite part;

FIG. 2 is a perspective cross-sectional view taken along line 2-2 ofFIG. 1 showing the molding component with a resin input port, a vacuumoutput port, a resin distribution channel, a standoff having a pluralityof passages, and a perimeter seal;

FIG. 3 shows a close-up view of the passages of the standoff;

FIG. 4 is a side elevational view of the cross-section of FIG. 2 showinga reinforcement material integrated into the molding component;

FIG. 5 is a side elevational view of the cross-section of FIG. 2 showinga region of the molding component having an increased thickness ascompared to other areas of the component;

FIG. 6 is a side elevational cross-sectional view of another embodimentof the molding component of the present invention having a doubleperimeter seal; and

FIG. 7 is a bottom perspective close-up view of one embodiment of theperimeter seal.

DETAILED DESCRIPTION OF THE INVENTION

The present invention improves on the materials and techniquesimplemented in traditional vacuum bag molding by providing, in a closedmolding process, a flexible molding component or tool configured for usewith a base mold tool to form a fiber reinforced composite part. Withreference to FIG. 1, a flexible molding component 10 is shown in usewith a base mold 100—in this particular example, a rigid female mold—toform a closed molding tooling system 200 for part fabrication. The basemold 100 may also be referred to as an “A” surface tool while themolding component 10 may also be referred to as a “B” surface tool,regardless of which surface tool would be considered either a male moldor a female mold is a specific tooling configuration.

The molding component 10, seen in more detail in FIG. 2, is formed of aflexible body structure 12 having integrally formed therewith one ormore resin input ports 14 for delivering resin (e.g., polyester resin)to an enclosed space 300 defined between the body structure 12 and thebase mold 100 where a fiber lay up (e.g., fiberglass or other fiber) isdisposed, and one or more vacuum output ports 16 for drawing the bodystructure 12 into contact with a surface 102 of the base mold 100 toshape resin/fiber combination into a finished part. Additionally, on aninterfacing surface 17 of the component 10 which interfaces with asurface 102 of the base mold 100, one or more resin distributionchannels 19 and one or more vacuum distribution channels 21 are formedinto the surface 17 to promote the consistent flow of resin across andthrough the fiber lay up under the influence of a vacuum draw. As seenin FIG. 2, the resin distribution channels 19 may provide fluidcommunication between adjacent resin input ports 14, and likewise thevacuum distribution channels 21 may provide fluid communication betweenadjacent vacuum output ports 16. Additionally, in some molding processesconducted with an embodiment of system 200, either of the resindistribution channels 19 or the vacuum distribution channels 21 may beomitted from the component 10, so long as adequate resin flow and vacuumpressures may be achieved from having only one type of distributionchannel (i.e., resin or vacuum) incorporated into the component 10.

As those of skill in the art appreciate with respect to closed moldingtechniques, resin can be delivered to the molding component 10 forflowing from the center of the component 10 to the perimeter or edgethereof, or the resin can be flowed from the edge of the component 10towards the center thereof. The resin input ports 14 and vacuum outputports 16 are positioned according to the direction of resin flow isdesired. Additionally, any number of resin input ports 14 and vacuumoutput ports 16 may be used to accomplish resin flow. In the exemplaryarrangement shown in FIG. 1, a plurality of resin input ports 14 arespaced generally adjacent to a perimeter region 18 of the body structure12 with one vacuum output port 16 formed at a central region 20 of thebody structure 12 and optionally connected via the vacuum distributionchannel 21 to any number of other vacuum output ports. FIG. 2 also showsthe general pathway of resin into the system 200 (i.e., with arrow I) toflow across and through a fiber lay up positioned on the base moldsurface 102 and thereby impregnate the fiber to form a part P in theenclosed space 300, and the pull of the vacuum out of the system 200(i.e., with arrow 0) to provide the negative pressure necessary for theresin flow and remove air present in the enclosed space 300.

The flexible molding component 10 is engineered out of materials thatprovide significant advantages when compared to traditional “B” surfacetools (e.g., vacuum bags), achieving in a closed molding tooling systemthe fabrication of a part with high fiber-to-resin ratios. With suchratios, composite parts may be made stronger and lighter, which arehighly desirable characteristics for boat hulls, aircraft frames, andother moving objects. The component 10 is preferably formed of materialssuch as polyurea, polyurethane, a polyurea/polyurethane compound, orother materials with similar physical characteristics, including—unliketooling components made from polyester—a lack of natural bonding withresins used in the composite part fabrication process. These materialsmay also be of the aromatic, aliphatic or polyaspartic form. If thecomponent 10 materials are of the aliphatic or polyaspartic form, thenultraviolet light (UV) curing of the laminates or gel coats used in theresin/fiber combination to form the part P may be conducted within theenclosed space 300 of the system 200 without damaging the integrity ofthe component 10. UV curing is often desirable because of the fast curetimes of the part P and reduced chemical emissions as compared totraditional curing methods employing a catalyst. Polyurea, polyurethane,and polyurea/polyurethane compounds also provide the advantage of beingconfigurable in a tooling component to have a broad range of hardnessesand percent elongation under force. This allows for greater flexibilityin part fabrication, including the changing of a fabricated part'sdimensional specifications without modifying or replacing the flexiblemolding component 10.

Various embodiments of the structure of the flexible molding component10 are shown in more detail in FIGS. 2-7. One resin input port 14 andone vacuum output port 16 are sectioned to show the path of resin flowin the system 200. The flexible body structure 12 is preferablyconfigured to have at least one perimeter seal 22 formed in theperimeter region 18, and, in the embodiments of FIGS. 2-5, a standoff 26extending from the interfacing surface 17. Alternatively, the perimeterseal 22 could be replaced by an external seal attachable to the flexiblebody structure 12 in the perimeter region 18.

The standoff 26 extends laterally across the interfacing surface 17generally for the width of the flexible body structure 12 and has a setof recessed passages 28 formed therein. The function of the standoff 26is to provide support to the body structure 12 when the vacuum isapplied thereto such that the structure 12 is not drawn so tightlyagainst the base mold surface 102 that resin flow from the resin inputport 14 to the vacuum output port 16 via the resin distribution channels19 and vacuum distribution channels 21, across and through a fiber layup, is not impeded. The passages 28, therefore, are needed for the resinto pass through the standoff 26 and flow in the direction of the vacuumdraw. Those of skill in the art will appreciate that resin and vacuumdistribution channel 19, 21 layouts other than those shown in FIGS. 4-6may be implemented with system 200 and used in conjunction with thestandoff 26 depending on the specific flow characteristics desired forthe resin.

One exemplary standoff 26 arrangement is shown in FIG. 3 formed bydownwardly extending teeth 30 of the standoff 26 defining the set oflaterally extending passageways 28; however any form of passageway, suchas apertures extending through the standoff 26, may be implemented solong as the standoff structure (e.g., teeth 30) is rigid enough tosupport the integrity of the passageways 28 when a vacuum is applied tothe body structure 12 and the passageways 28 have a sufficientcross-sectional area as to allow enough resin to flow to the fiber layup in a set amount of part fabrication time.

The perimeter seal 22 extends completely around the perimeter of thebody structure 12 to sealingly engage the base mold surface 102 and formthe enclosed space 300 containing the materials for the part. The seal22 is essentially a downward extension 32 from the body structure 12transitioning from a sloped surface 34 to an abutting surface 36. Theabutting surface 36 can be a flat surface or other surface shape havinga contour that is the same as the contour of the base mold surface inthat region, or as shown in FIG. 7, the surface 36 may be formed as agrid of sidewall flanges 38. These flanges 38 are formed by recessingareas 40 of the seal 22 to create a series of voids 42. Upon drawing ofthe vacuum in the system 200, the flanges 38 are configured to flexsufficiently enough to have a good seal with the base mold surface 102to create the negative pressure necessary to move the interfacingsurface 24 into solid contact with the part P and the base mold 100, butto have enough rigidity as to not fully collapse into the voids 42 andplace excessive compressive forces on the standoff 26, which couldimpede the flow of resin through the passages 28. The entire perimeterseal 22 may have a consistent modulus of elasticity, or alternatively,regions of the seal above the flanges 38 may have a higher modulus ofelasticity than the flanges 38 themselves, which aids in the flexing ofthe flanges 38 to create an adequate seal. Still further, the flanges 38and voids 42 create attachment points where various tools may be securedto the molding component 10 to more easily move the component onto andoff of the base mold 100.

FIG. 4 shows another arrangement where reinforcing material 44 is moldedor otherwise integrated into the body structure 12 to create regions ofthe flexible molding component having varying physical properties, forexample, varying densities, rigidities, and compression and elongationcharacteristics. For example, it may be desired for regions adjacent tothe resin input port 14 and vacuum output port 16 to have an increasedrigidity, such that when the vacuum is applied to the system 200 tosealingly engage the perimeter seal 22 with the base mold 100 and drawthe interfacing surface 24 against the resin/fiber combination and basemold surface 102, openings 46, 48 to the input and output ports 14, 16,respectively, remain structurally intact such that adequate resin flowand vacuum pressure is maintained. Examples of reinforcing materials mayinclude metals, such as aluminum, composites, or other materials. Theweight of the reinforcing material 44 may also be used to increase thepressure on the perimeter seal 22—based on the surface area of the seal22 that abuts the base mold 100. Configuring the seal 22 with sidewallflanges 38 further reduces the surface area of the seal 22, and incombination with the reinforcing material 44, work with the vacuum toprovide a substantial clamping force with the base mold 100 to furthermaintain the integrity of the vacuum pressure during the fabricationprocess and prevent gaseous materials from leaking out of the enclosedspace 300 and into the surrounding environment. Also, similar to theflanges 34 of the perimeter seal 22, the reinforcing material mayprovide attachment points where various tools may be secured to themolding component 10 to more easily move the component onto and off ofthe base mold 100, which is a significant advantage when the component10 is large.

Another configuration of the flexible molding component 10 is shown inFIG. 5 where the body structure 12 has a region 50 of increasedthickness. This region 50 therefore has varying physical properties ascompared to other regions of the body structure 12, and can impartdifferent physical properties onto a region of the fabricated part belowthe component region 50. For example, by having the increased thicknessregion 50, the weight thereof forces the component 10 to better conformto the surface contours of the base mold surface 102 immediately belowregion 50 and thereby more accurately shape the part P to the desiredcontour.

FIG. 6 shows yet another embodiment of the flexible molding component10. This embodiment of the component is similar to that shown FIG. 2,but the body structure is formed with dual perimeter seals 22 extendingdownward from the interfacing surface 17 preferably in the form oftapered flanges. The resin input port 14 shown in section in FIGS. 2, 4and 5 is replace by a perimeter-sealing vacuum output port 16′ which isin fluid communication with vacuum distribution channel 21 extendinggenerally around the perimeter of the body structure 12 between the dualperimeter seals 22. Multiple perimeter-sealing vacuum output ports 16′may be positioned to fluidly communicate with the vacuum distributionchannel 21. The purpose of the dual perimeter seals 22 configuration isto facilitate the improved locking of the flanges against the base moldsurface 102 when the vacuum is applied through the perimeter-sealingvacuum output port 16′, because the vacuum draw for the perimeter sealsis independent of the vacuum draw by the vacuum output port 16 directingthe flow of the resin, it can be set at higher vacuum levels than theresin vacuum port 16. This improved locking or sealing also allows forresin to be introduced through one or more resin input ports 14—whichare preferably not in fluid communication with the vacuum distributionchannel 21—into the enclosed space 300 at moderate injection pressuresto “push” the resin across and through the fiber lay up on the base moldsurface 102 in addition to the vacuum output port 16 draw of the resin.This method will thereby increase the speed of part fabrication bymoving the resin through the fiber lay up more quickly. As parts becomelarger, this speed advantage becomes even more pronounced. Further, aswith the perimeter-sealing vacuum output ports 16′, multiple resin inputports 14 may be provided on the body structure 12, and with resindistribution channels 19, for better resin distribution as needed.

It should also be understood that the flexible molding component 10 mayalso be used to produce fiber reinforced composite parts withoutinjecting or otherwise introducing the resin between the body structure12 and the base mold 100 through the resin input ports 14. Instead, theresin may be poured, rolled or sprayed onto the fiber lay up lying onthe base mold surface 102 using well-known methods, and then thecomponent 10—without resin input ports 14—is moved onto the base moldsurface 102 to enclose the resin/fiber combination and the vacuum outputports 16 (or other vacuum means) apply the vacuum draw to remove air andexcess resin in the enclosed space 300 of the system 200 and formed thefinished part P.

Therefore, it can be seen that the flexible molding component 10 of thepresent invention provides a superior molding tool for reliablyproducing increased strength fiber reinforced composite parts in aclosed molding tooling system 200. The flexible nature of the integrallyformed molding component 10 avoids the necessity in the prior art ofconducting the labor intensive and exacting process of building uppatterns to produce a molding tool that can fabricate a part having aspecific thickness. The system 200 can also be used to apply uniformpressure over virtually any size or type of surface that might requiresuch pressure to form the finished P with the desired shape andmechanical properties. This uniform pressure application is madepossible by the configurable nature of the resin input ports 14 andvacuum output ports 16—which may be placed at customized locations onthe body structure 12—and the flexible nature of the body structure 12.Furthermore, since certain changes may be made in the above inventionwithout departing from the scope hereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingbe interpreted as illustrative and not in a limiting sense. It is alsoto be understood that the following claims are to cover certain genericand specific features described herein.

1. A mold component configured for use with a base mold in a closedmolding process to form a fiber reinforced composite part, the moldcomponent comprising: a flexible body structure including a perimeterregion and an interfacing surface, at least a portion of the interfacingsurface configured to contact the part disposed on the base mold, andthe flexible body structure having integrally formed therewith: one ormore distribution channels extending across the interfacing surface; andone or more perimeter seals extending from the perimeter region forsealing engagement with the base mold to enclose the part between thebody structure and the base mold.
 2. The mold component of claim 1,wherein the one or more perimeter seals comprise a plurality ofperimeter seals extending downward from the body structure and defininga vacuum distribution channel therebetween.
 3. The mold component ofclaim 1, wherein the one or more distribution channels comprise: one ormore resin distribution channels; and one or more vacuum distributionchannels.
 4. The mold component of claim 3, further comprising: astandoff extending from the interfacing surface of the body structure;and a plurality of passages formed in the standoff to facilitate fluidcommunication between the one or more resin distribution channels and anenclosed space formed between the body structure and the base mold wherethe fiber reinforced composite part may be formed.
 5. The mold componentof claim 1, wherein the flexible body structure is formed of one or morematerial selected from the group consisting of polyurea, polyurethaneand a polyurea/polyurethane compound.
 6. The mold component of claim 5,wherein the flexible body structure is further formed as one of analiphatic, aromatic or polyaspartic compound.
 7. The mold component ofclaim 1, wherein the one or more perimeter seals comprise a grid ofsidewall flanges.
 8. The mold component of claim 1, wherein the bodystructure further comprises first regions formed at the one or moredistribution channels having increased rigidity as compared to theremainder of the body structure.
 9. The mold component of claim 8,wherein the first regions include a reinforcing material bonded with thebody structure.
 10. The mold component of claim 1, wherein the compositepart requires varying mold surface conformities and molding pressuresfor its formation, and wherein the body structure is formed of one ormore materials having varying physical properties so that the physicalproperties of the body structure correspond to the physical propertiesrequired for the formation of the composite part.
 11. The mold componentof claim 10, wherein physical properties include one or more of thefollowing: density, rigidity, compression and elongation.
 12. The moldcomponent of claim 1, further comprising: one or more resin input portsextending through the body structure and in fluid communication with atleast one of the one or more resin distribution channels; and one ormore vacuum output ports extending through the body structure and influid communication with at least one of the one or more vacuumdistribution channels.
 13. A mold component configured for use with abase mold in a closed molding process to form a fiber reinforcedcomposite part, the mold component comprising: a flexible unitary bodyhaving one or more perimeter seals and an interfacing surface upon whichone or more distribution channels are formed; wherein the unitary bodyis formed substantially of one or more materials selected from the groupconsisting of polyurea, polyurethane and a polyurea/polyurethanecompound.
 14. The mold component of claim 13, wherein the one or moreperimeter seals comprise a plurality of perimeter seals extendingdownward from the unitary body and defining a vacuum distributionchannel therebetween.
 15. The mold component of claim 13, wherein theone or more distribution channels comprise: one or more resindistribution channels; and one or more vacuum distribution channels. 16.The mold component of claim 15, wherein at least a portion of theinterfacing surface is configured to contact the part disposed on thebase mold, the mold component further comprising: a standoff extendingfrom the interfacing surface of the unitary body; and a plurality ofpassages formed in the standoff to facilitate fluid communicationbetween the one or more resin distribution channels and an enclosedspace formed between the unitary body and the base mold where the fiberreinforced composite part may be formed.
 17. The mold component of claim13, wherein the unitary body is further formed as one of an aliphatic,aromatic or polyaspartic compound.
 18. The mold component of claim 13,wherein the one or more perimeter seals comprises a grid of sidewallflanges.
 19. The mold component of claim 13, wherein the unitary bodyfurther comprises first regions formed at the one or more distributionchannels having increased rigidity as compared to the remainder of thebody structure.
 20. The mold component of claim 19, wherein the firstregions include a reinforcing material bonded with the unitary body. 21.The mold component of claim 13, wherein the composite part requiresvarying mold surface conformities and molding pressures for itsformation, and wherein the material forming the unitary body has varyingphysical properties so that the physical properties of the unitary bodycorrespond to the physical properties required for the formation of thecomposite part.
 22. The mold component of claim 21, wherein physicalproperties include one or more of the following: density, rigidity,compression and elongation.
 23. The mold component of claim 13, furthercomprising: one or more resin input ports extending through the unitarybody and in fluid communication with at least one of the one or moreresin distribution channels; and one or more vacuum output portsextending through the unitary body and in fluid communication with atleast one of the one or more vacuum distribution channels.
 24. In aclosed molding system for forming a fiber reinforced composite part, thesystem including an A surface mold tool and a B surface mold tool, theimprovement comprising: the B surface mold tool comprising a flexiblebody structure including a perimeter region and an interfacing surface,at least a portion of the interfacing surface configured to contact thepart disposed on the base mold, and the flexible body structure havingintegrally formed therewith: one or more distribution channels extendingacross the interfacing surface; and one or more perimeter sealsextending from the perimeter region for sealing engagement with the basemold to enclose the part between the body structure and the base mold.25. The system of claim 24, wherein the one or more distributionchannels comprise: one or more resin distribution channels; and one ormore vacuum distribution channels.
 26. The system of claim 25, furthercomprising: a standoff extending from the interfacing surface of thebody structure; and a plurality of passages formed in the standoff tofacilitate fluid communication between the one or more resindistribution channels and an enclosed space formed between the bodystructure and the base mold where the fiber reinforced composite partmay be formed.
 27. The system of claim 24, wherein the flexible bodystructure is formed of a material selected from the group consisting ofpolyurea, polyurethane and a polyurea/polyurethane compound.
 28. Thesystem of claim 24, wherein the B surface mold tool requires varyingmold surface conformities and molding pressures for its formation, andwherein the body structure is formed of one or more materials havingvarying physical properties so that the physical properties of the bodystructure correspond to the physical properties required for theformation of the composite part.
 29. The system of claim 28, whereinphysical properties include one or more of the following: density,rigidity, compression and elongation.
 30. The system of claim 28,further comprising: one or more resin input ports extending through theunitary body and in fluid communication with at least one of the one ormore resin distribution channels; and one or more vacuum output portsextending through the unitary body and in fluid communication with atleast one of the one or more vacuum distribution channels.
 31. A processinvolving closed molding tooling techniques to form a fiber reinforcedcomposite part against a base mold with a flexible body structure havingan interfacing surface upon which one or more distribution channels areformed, and one or more perimeter seals, the process comprising: placinga fiber lay up on the base mold; moving the body structure onto the basemold such that the fiber lay up is covered by the interfacing surface ofthe body, thereby forming an enclosed space between the body structureand the base mold, the fiber lay up being located in the enclosed space;and dispensing resin into the enclosed space and drawing a vacuumthrough the enclosed space to cause the one or more perimeter seals tosealingly engage the base mold, the interfacing surface of the unitarybody to urge the fiber lay up to be shaped to the base mold, and theresin to travel through the one or more distribution channels and acrossand through the fiber lay up generally in the direction of the vacuumdraw to thereby form the composite part upon curing.
 32. The process ofclaim 31, wherein the body structure is formed substantially of amaterial selected from the group consisting of polyurea, polyurethaneand a polyurea/polyurethane compound.
 33. The process of claim 31,wherein the one or more perimeter seals comprise a plurality ofperimeter seals extending downward from the body structure and defininga vacuum distribution channel therebetween.
 34. The process of claim 31,wherein the one or more distribution channels comprise: one or moreresin distribution channels; and one or more vacuum distributionchannels.
 35. The process of claim 34, further comprising: a standoffextending from the interfacing surface of the body structure; and aplurality of passages formed in the standoff to facilitate fluidcommunication between the one or more resin distribution channels andthe enclosed space.
 36. The process of claim 31, wherein the bodystructure further comprises first regions formed at the one or moredistribution channels having varying physical properties as compared tothe remainder of the body structure.
 37. The process of claim 36,wherein the varying physical properties include one or more of thefollowing: density, rigidity, compression and elongation.
 38. Theprocess of claim 36, wherein the first regions include a reinforcingmaterial bonded with the body structure.
 39. The process of claim 31,wherein resin is dispensed into the enclosed space through one or moreresin input ports extending through the body structure, the vacuum isdrawn through the enclosed space through one or more vacuum output portsextending through the body structure.
 40. A process involving closedmolding tooling techniques to form a fiber reinforced composite partagainst a base mold with a flexible body structure having an interfacingsurface upon which one or more distribution channels are formed, and oneor more perimeter seals, the process comprising: placing a fiber lay upon the base mold; applying resin onto the fiber lay up; moving theunitary body onto the base mold such that the fiber lay up/resincombination is covered by the interfacing surface of the body structure;and drawing a vacuum through the enclosed space to cause the one or moreperimeter seals to sealingly engage the base mold, the interfacingsurface of the unitary body to urge the fiber lay up to be shaped to thebase mold, and the resin to travel through the one or more distributionchannels and across and through the fiber lay up generally in thedirection of the vacuum draw to thereby form the composite part uponcuring.